Added "@BotMention slm" command
Added "@BotMention slm" command

- slm shows the last message you were mentioned in. Useful if you don't
want to scroll up just to see where is the message you need to read.

kyoryo/DiscordBot,Nielk1/NadekoBot,Uleyethis/FightBot,miraai/NadekoBot,Midnight-Myth/Mitternacht-NEW,PravEF/EFNadekoBot,Midnight-Myth/Mitternacht-NEW,dtshady/NadekoBot,justinkruit/WIABot,powered-by-moe/MikuBot,rumlefisk/NadekoBot,DevNub/NadekoBot,blitz4694/NadekoBot,Taknok/NadekoBot,N1SMOxGT-R/NeoBot,Wizkiller96/WizBot-Updated,ScarletKuro/NadekoBot,kyoryo/DiscordBot,Blacnova/NadekoBot,kyoryo/DiscordBot,shikhir-arora/NadekoBot,Midnight-Myth/Mitternacht-NEW,Wizkiller96/WizBot-Updated,Grinjr/NadekoBot,Youngsie1997/NadekoBot,Track44/Nadeko,WoodenGlaze/NadekoBot,ShadowNoire/NadekoBot,gfrewqpoiu/NadekoBot,blitz4694/NadekoBot,DevNub/NadekoBot,dtshady/NadekoBot,N1SMOxGT-R/NeoBot,justinkruit/DiscordBot,halitalf/NadekoMods,Reiuiji/NadekoBot,Midnight-Myth/Mitternacht-NEW